Thermal And Statistical Properties of X-rayBright Points

摘要

HINODE's X-ray Telescope (XRT) offers a unique combination of high spatial 2")and thermal resolution, full-Sun observations of the solar corona over a wide range of temperatures(5.8 ti < log T < 7.6). We use multi-filter Hinode/XRT data to explore the thermal,statisticaland spatial properties of X-ray bright points (XBPs). We have developed an automated XBP finderto study BPs over two periods during November 2007 and May 2008. We detect somewhat fewerXBPs than SOHO EIT in 195 A but find comparable values to the 284 A band. This is likely duein some part to the somewhat stricter requirements on XBP shape and enhancement above localbackground that we have adopted. We find that most XBPs appear to be relatively cool on average(log T 6.1), only slightly hotter than the average quiet Sun. There is a trend for larger XBPs tobe hotter, with a sub-class of XBPs which are hotter still at all sizes. We further investigate thespatial distribution of XBPs, in particular exploring whether the "overhot" XBPs have any tendencyto appear in or near coronal holes. We find that there appears to be a notable trend of overhot brightpoints within the two data sets and a tendency of those to lie within 40" of coronal holes.